Pernicious Anemia
In this patient, the elevated serum gastrin level and the presence of antiintrinsic factor antibodies pointed to pernicious anemia.
The term pernicious anemia, which was coined by a German physician in the 19th century, is somewhat misleading. The modern definition is vitamin B12 deficiency caused by B12 malabsorption that results from a dearth of gastric intrinsic factor. The key to the disease is the lack of intrinsic factor-a gastrointestinal finding, not a hematologic one. As many as a third of patients in whom the gastric defect is diagnosed do not have megaloblastic anemia. In other words, nonanemic patients can have pernicious anemia.
It is thought to be an autoimmune disorder that results in antibody production against both intrinsic factor and the gastric parietal cells that make the factor. About 80% of patients with pernicious anemia have antibodies against parietal cells, and about 66% have antibodies against intrinsic factor. Parietal cell antibodies are not specific for pernicious anemia; they can occur in any patient with type A atrophic gastritis, a condition that is especially common in the elderly. Thus, parietal cell antibody testing is not appropriate for the diagnosis of pernicious anemia. Intrinsic factor antibody testing, on the other hand, is about 95% specific for pernicious anemia but has a low sensitivity.
Comments
There is pancytopenia and the indices of RBC are macrocytic so in this setting the first Q is megaloplastic or non megaloplastic? and the answer is easy by see hypersegmented neutrophil in peripheral blood film or bone marrow second Q is if megaloplastic what is the cause folate or B12 deficiency and what is the cause of that? if non megaloplastic we have to rule out autoimmune hemolytic anemia, mylodysplastic syndromes, hypothyroidism.
She has gradual onset of anemic symptoms Her CBC shows macrocytic [MCV.95fl],increased RDW .Platelets counts m/b reduced(<100,000/mm3).No h/o recent bleeding exclude IDA.Jaundice exclude haemolytic .Medication with methotrexate, exclude folic acid B12 deficiency.Alcoholism exclude folic acid def.Hospitalization exclude b12 def in gastric operation.Normal BUN exclude anemia of chronic disease. Dx is probably megaloblastic anemia due to combined f/a and B12 deficiency with underlying hypovitaminosis,antimetabolytes, copper deficiency with zinc excess.Bone marrow will show megaloblasts and hypersegmented neutrophils.
Diagnosis is must before blood transfusion in this case
megaloblastic anemia
mostly pernious anaemia